Ethan Hunt and his IMF team face a new threat: an AI called Ares that wants to unleash chaos on the world. To stop her, they must find a key that can activate or deactivate a secret weapon. Along the way, they cross paths with old enemies and allies, such as arms dealer Alanna Mitsopolis and MI6 agent Ilsa Faust. The mission becomes complicated when Ethan discovers that Ares has a personal connection to him and that his past may be his greatest weakness.